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Question
The binary operation * : R × R → R is defined as a * b = 2a + b. Find (2 * 3) * 4.
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Solution
As, a * b = 2a + b
So, (2 * 3) * 4 = [2(2) + 3] * 4
= [4 + 3] * 4
= 7 * 4
= 2(7) + 4
= 14 + 4
= 18
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